659
FXUS64 KHUN 251427
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
927 AM CDT Sat May 25 2024

...New NEAR TERM...

.NEAR TERM...
(Rest of Today)
Issued at 927 AM CDT Sat May 25 2024

The early morning system prompting a severe thunderstorm warning
has decreased in intensity and continued east beyond the AL
border. In its wake, current satellite and surface obs indicate
significant clearing with morning temps already rising into the
high 60s to low 70s. Partly cloudy to mostly clear skies will
likely develop through the next several hours yielding high temps
in the mid to high 80s.

The sunny, warm, and moist conditions developing throughout the
day will prime out local environment for the potential for
additional strong to severe storms this afternoon. The severe
threat will be highly conditional as it will be contingent on
several small elements and how they evolve throughout the day.
Storms will be diurnally driven meaning stronger surface heating
throughout the day will create a better environment for storms to
live in. The uncertainty remains in exactly when, where, and if,
storms will initiate. A likely scenario right now appears that
afternoon storms will initiate along lingering outflow boundaries
from morning convection. Where those outflow boundaries set up
will give us a better idea as to if our CWA will remain mostly
clear or see isolated strong to severe storms.

Any storms that do initiate or drift into our area will pose a
threat for damaging winds, hail, and frequent lightning. Damaging
wind will be our primary threat as the afternoon environment looks
favorable for downbursts. Fortunately the tornado threat will
greatly diminish throughout the afternoon as our shear will
steadily decrease throughout the day. Regardless of confidence in
threats, make sure to have multiple ways to receive warnings and
remain weather aware as even small storms can produce frequent
lighting.

&&

.SHORT TERM...
(Tonight through Tuesday)
Issued at 359 AM CDT Sat May 25 2024

The potential for microbursts will continue into the evening
hours before subsiding with the loss of diurnally driven
instability around sunset. Overnight, a break in rainfall will
take place for most of the TN Valley. However, low chances (around
30% or less) have been kept in due to lingering showers.

Sunday into Monday, high sfc pressure off the southern coast of
Florida will cause southerly winds to advect moisture from the
Gulf to the Tennessee Valley. This will support increased dew
points and subsequently an increased heat risk (to be discussed at
the end of this short term section) ahead of a cold front. A
slight risk (level 2/5) is in place for most of the area
(primarily north of the TN River). Timing continues to shift
later, however, it is looking like storms will move in from the NW
around 1 AM CDT and continue southeastward through noon. These
storms will bring risks of damaging winds (medium confidence),
heavy rainfall/localized flash flooding (medium confidence), hail
(medium confidence), and one or two tornadoes (low confidence).
Forecast soundings currently have us capped overnight, however,
there is sufficient shear in place as well as low level
streamwise vorticity to support a relatively higher tornado risk
if that cap is broken. Steep mid level lapse rates (7-8 C/km) and
MUCAPE around 1700-1900 J/kg will also support a hail risk.
DCAPE around 900-1100 J/kg also exists in these model soundings,
accompanied by sufficient shear to warrant a damaging wind risk.
We will continue to monitor this system closely.

As mentioned previously, high dew points will contribute to an
increased, moderate heat risk with high temperatures forecast to
reach the low 90s Sunday. During this time, heat will affect
individuals most sensitive to heat, especially those without
effective cooling and/or adequate hydration. Max heat indices
during this period will be around 95-99 degrees F.

Overnight Monday into Tuesday, dry weather returns (PoPs 10% or
less) as high pressure filters in from the northwest and lows
drop into the 60s before rising back into the low to mid 80s
during Tuesday afternoon.

&&

.LONG TERM...
(Tuesday night through Friday)
Issued at 359 AM CDT Sat May 25 2024

Sfc high pressure allows for dry weather to settle over the
region through the mid week. Upper level shortwaves will allow a
very low chance of showers (10% or less) during this time,
however, confidence is low in this occurring. High temperatures
during this period are forecast to be in the 80s with overnight
lows in the 50s/60s.

&&

.AVIATION...
(12Z TAFS)
Issued at 640 AM CDT Sat May 25 2024

A line of storms will continue to push eastward out of the area
this morning. Additional development is possible later this
afternoon and evening but confidence in timing and placement
remains too low to warrant more than a PROB30 at this time.
Otherwise, VFR conditions prevail.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...None.
TN...None.
&&

$$

NEAR TERM...RAD
SHORT TERM....HC
LONG TERM....HC
AVIATION...30